title: Estimating body fat in NCAA Division I female athletes: a five-compartment model validation of laboratory methods.
abstract: The purpose of the present study was to determine the validity of various laboratory methods for estimating percent body fat (%fat) in NCAA Division I college female athletes (n = 29; 20 +/- 1 year). Body composition was assessed via hydrostatic weighing (HW), air displacement plethysmography (ADP), and dual-energy X-ray absorptiometry (DXA), and estimates of %fat derived using 4-compartment (C), 3C, and 2C models were compared to a criterion 5C model that included bone mineral content, body volume (BV), total body water, and soft tissue mineral. The Wang-4C and the Siri-3C models produced nearly identical values compared to the 5C model (r > 0.99, total error (TE) < 0.40%fat). For the remaining laboratory methods, constant error values (CE) ranged from -0.04%fat (HW-Siri) to -3.71%fat (DXA); r values ranged from 0.89 (ADP-Siri, ADP-Brozek) to 0.93 (DXA); standard error of estimate values ranged from 1.78%fat (DXA) to 2.19%fat (ADP-Siri, ADP-Brozek); and TE values ranged from 2.22%fat (HW-Brozek) to 4.90%fat (DXA). The limits of agreement for DXA (-10.10 to 2.68%fat) were the largest with a significant trend of -0.43 (P < 0.05). With the exception of DXA, all of the equations resulted in acceptable TE values (<3.08%fat). However, the results for individual estimates of %fat using the Brozek equation indicated that the 2C models that derived BV from ADP and HW overestimated (5.38, 3.65%) and underestimated (5.19, 4.88%) %fat, respectively. The acceptable TE values for both HW and ADP suggest that these methods are valid for estimating %fat in college female athletes; however, the Wang-4C and Siri-3C models should be used to identify individual estimates of %fat in this population.
authors.affiliation: Metabolic and Body Composition Laboratories, Department of Health and Exercise Science, University of Oklahoma, 115 Huston Huffman Center, 1401 Asp Ave, Norman, OK, 73019, USA.
authors.forename: Jordan R
authors.initials: JR
authors.lastname: Moon
authors.forename: Joan M
authors.initials: JM
authors.lastname: Eckerson
authors.forename: Sarah E
authors.initials: SE
authors.lastname: Tobkin
authors.forename: Abbie E
authors.initials: AE
authors.lastname: Smith
authors.forename: Christopher M
authors.initials: CM
authors.lastname: Lockwood
authors.forename: Ashley A
authors.initials: AA
authors.lastname: Walter
authors.forename: Joel T
authors.initials: JT
authors.lastname: Cramer
authors.forename: Travis W
authors.initials: TW
authors.lastname: Beck
authors.forename: Jeffrey R
authors.initials: JR
authors.lastname: Stout
mesh_terms: D015502:Absorptiometry, Photon / Q000379:methods*; D000273:Adipose Tissue / Q000033:anatomy & histology*; D000886:Anthropometry / Q000379:methods; D001823:Body Composition / Q000502:physiology*; D005260:Female; D006801:Humans; D010991:Plethysmography / Q000379:methods*; D015203:Reproducibility of Results; D013177:Sports; D055815:Young Adult